US9410438B2 - Dual rotor blades having a metal leading airfoil and a trailing airfoil of a composite material for gas turbine engines - Google Patents
Dual rotor blades having a metal leading airfoil and a trailing airfoil of a composite material for gas turbine engines Download PDFInfo
- Publication number
- US9410438B2 US9410438B2 US13/789,794 US201313789794A US9410438B2 US 9410438 B2 US9410438 B2 US 9410438B2 US 201313789794 A US201313789794 A US 201313789794A US 9410438 B2 US9410438 B2 US 9410438B2
- Authority
- US
- United States
- Prior art keywords
- component
- rotor blade
- blade
- airfoil
- rotor
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active, expires
Links
- 229910052751 metal Inorganic materials 0.000 title claims abstract description 26
- 239000002184 metal Substances 0.000 title claims abstract description 26
- 239000002131 composite material Substances 0.000 title claims abstract description 18
- 230000009977 dual effect Effects 0.000 title claims description 22
- 239000007787 solid Substances 0.000 claims description 7
- 239000000463 material Substances 0.000 claims description 6
- 230000003628 erosive effect Effects 0.000 claims description 5
- 239000010936 titanium Substances 0.000 claims description 5
- 229920000049 Carbon (fiber) Polymers 0.000 claims description 4
- RTAQQCXQSZGOHL-UHFFFAOYSA-N Titanium Chemical compound [Ti] RTAQQCXQSZGOHL-UHFFFAOYSA-N 0.000 claims description 4
- 239000004917 carbon fiber Substances 0.000 claims description 4
- 229920001971 elastomer Polymers 0.000 claims description 4
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 claims description 3
- 239000004593 Epoxy Substances 0.000 claims description 3
- 229910001200 Ferrotitanium Inorganic materials 0.000 claims description 3
- 239000002041 carbon nanotube Substances 0.000 claims description 3
- 229910021393 carbon nanotube Inorganic materials 0.000 claims description 3
- 239000000806 elastomer Substances 0.000 claims description 3
- 239000002952 polymeric resin Substances 0.000 claims description 3
- 229910001220 stainless steel Inorganic materials 0.000 claims description 3
- 239000010935 stainless steel Substances 0.000 claims description 3
- 229920003002 synthetic resin Polymers 0.000 claims description 3
- 229920005989 resin Polymers 0.000 claims description 2
- 239000011347 resin Substances 0.000 claims description 2
- 150000002739 metals Chemical class 0.000 claims 1
- 230000008901 benefit Effects 0.000 description 3
- 230000000712 assembly Effects 0.000 description 2
- 238000000429 assembly Methods 0.000 description 2
- 230000006872 improvement Effects 0.000 description 2
- 238000000034 method Methods 0.000 description 2
- 238000012986 modification Methods 0.000 description 2
- 230000004048 modification Effects 0.000 description 2
- 229910052719 titanium Inorganic materials 0.000 description 2
- 230000008859 change Effects 0.000 description 1
- 230000002708 enhancing effect Effects 0.000 description 1
- -1 for example Substances 0.000 description 1
- VNWKTOKETHGBQD-UHFFFAOYSA-N methane Chemical compound C VNWKTOKETHGBQD-UHFFFAOYSA-N 0.000 description 1
- 230000009467 reduction Effects 0.000 description 1
- 238000011144 upstream manufacturing Methods 0.000 description 1
Images
Classifications
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
- F01D—NON-POSITIVE DISPLACEMENT MACHINES OR ENGINES, e.g. STEAM TURBINES
- F01D5/00—Blades; Blade-carrying members; Heating, heat-insulating, cooling or antivibration means on the blades or the members
- F01D5/12—Blades
- F01D5/28—Selecting particular materials; Particular measures relating thereto; Measures against erosion or corrosion
- F01D5/282—Selecting composite materials, e.g. blades with reinforcing filaments
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
- F01D—NON-POSITIVE DISPLACEMENT MACHINES OR ENGINES, e.g. STEAM TURBINES
- F01D5/00—Blades; Blade-carrying members; Heating, heat-insulating, cooling or antivibration means on the blades or the members
- F01D5/12—Blades
- F01D5/14—Form or construction
- F01D5/141—Shape, i.e. outer, aerodynamic form
- F01D5/146—Shape, i.e. outer, aerodynamic form of blades with tandem configuration, split blades or slotted blades
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
- F04D—NON-POSITIVE-DISPLACEMENT PUMPS
- F04D29/00—Details, component parts, or accessories
- F04D29/26—Rotors specially for elastic fluids
- F04D29/32—Rotors specially for elastic fluids for axial flow pumps
- F04D29/321—Rotors specially for elastic fluids for axial flow pumps for axial flow compressors
- F04D29/324—Blades
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F05—INDEXING SCHEMES RELATING TO ENGINES OR PUMPS IN VARIOUS SUBCLASSES OF CLASSES F01-F04
- F05D—INDEXING SCHEME FOR ASPECTS RELATING TO NON-POSITIVE-DISPLACEMENT MACHINES OR ENGINES, GAS-TURBINES OR JET-PROPULSION PLANTS
- F05D2220/00—Application
- F05D2220/30—Application in turbines
- F05D2220/36—Application in turbines specially adapted for the fan of turbofan engines
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02T—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO TRANSPORTATION
- Y02T50/00—Aeronautics or air transport
- Y02T50/60—Efficient propulsion technologies, e.g. for aircraft
-
- Y02T50/672—
-
- Y02T50/673—
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
- Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
- Y10T29/00—Metal working
- Y10T29/49—Method of mechanical manufacture
- Y10T29/49316—Impeller making
- Y10T29/49332—Propeller making
Definitions
- the described subject matter relates generally to gas turbine engines, and more particularly to rotor blades.
- Fan blades are made of metal, such as titanium. Fan blades, of this type, are capable of withstanding the temperatures to which they are exposed, erosion resistance and have a relatively good chance of surviving impact with foreign bodies, such as bird strikes, without seriously affecting engine performance. Metal blades, however, are relatively heavy and so increase the overall weight of the engine and reduce its performance. Efforts have been made, therefore, in recent years to develop blades made of alternative, lighter materials such as composite materials, for example, carbon fiber epoxy composites. The problem with such composite blades is that they are not as robust as metal blades and are more easily damaged by contact with foreign objects.
- a rotor blade for a gas turbine engine comprising a first airfoil component extending radially between a root and a tip and a second airfoil component, separate from the first airfoil component, extending radially between a root and a tip, wherein the second airfoil component is downstream, in series, of the first airfoil component and at least the first airfoil component is made of metal.
- a fan for a turbo fan engine comprising an array circumferentially spaced transonic dual rotor blades with each dual rotor blade having a leading blade component and a separate trailing blade component arranged in series with the leading blade component; the leading blade component made of a metal to resist to foreign object damage and erosion, and the trailing blade component made of a relatively lighter material providing enhanced aerodynamic characteristics to the dual rotor blade such that the weight of the dual rotor blade is less than a similar rotor blade made of solid metal.
- a method of forming a rotor blade for a gas turbine engine comprising the steps of forming an annular base, mounting an array of dual rotor blade assemblies in a circumferential spaced apart arrangement on said base which each rotor blade assembly extending radially between a root on the base and a tip, the improvement including the steps of arranging in each dual rotor blade assembly a leading blade component selected from a metal and a trailing blade component selected from a suitable composite material suitable to reduce the weight of the rotor assembly, in series relative to the leading blade component and adjusting the trailing rotor component to tune the dual rotor blade.
- a method of forming a rotor blade for a fan in a turbo fan turbine engine comprising the steps of forming an annular hub, mounting an array of rotor blade assemblies in a circumferentially spaced apart arrangement on said hub which each rotor blade assembly extending radially between a root on the hub and a tip; the improvement including the steps of arranging in each rotor blade assembly a leading blade component selected from a metal suitable to withstand foreign object damage at transonic tip speeds and a trailing blade component selected from a suitable composite material suitable to reduce the weight of the rotor assembly, in series relative to the leading blade component and adjusting the trailing rotor component to tune the rotor blade.
- FIG. 1 is a schematic cross-sectional view of a fan type gas turbine engine
- FIG. 2 is an axial cross-section of a portion of the engine with a side view of a detail of a preferred embodiment
- FIG. 3 is a schematic cross section of the detail shown in FIG. 2 , at right angles thereto, showing a particular feature thereof;
- FIG. 4 is a schematic cross section of the detail shown in FIG. 2 , at right angles thereto, showing a different feature compared to FIG. 3 .
- FIG. 1 schematically depicts a turbofan engine A which, as an example, illustrates the application of the described subject matter.
- the turbofan engine A includes a nacelle 10 , a low pressure spool assembly which includes at least a fan 12 and a low pressure turbine 14 connected by a low pressure shaft 16 , and a high pressure spool which includes a high pressure compressor 18 and a high pressure turbine 20 connected by a tie-shaft 22 and a high pressure shaft 24 .
- the engine further comprises a combustor 26 .
- Advanced fans in turbofan engines are transonic with high rotor tip speeds. These transonic fans have to be strong enough to take a certain size of foreign object damage without a significant performance loss. At the same time, the reduction of weight is a key requirement for aircraft engine design.
- the fan 12 described in the following example combines the features of transonic rotor tip speed with relatively lower weight compared to fans with existing all-titanium fan blades.
- the fan 12 includes an array of circumferentially spaced dual rotor blades, each made up of leading rotor blade 32 and trailing rotor blade 34 .
- the leading rotor blade 32 is made of a strong metal such as titanium or stainless steel.
- Other equivalent or superior materials may also be contemplated, as long as the criteria of resistance to foreign object damage and resistance to erosion are maintained.
- the term “metal” is defined herein to include such equivalent or superior materials.
- the trailing rotor blade 34 is constructed of a lighter composite material.
- the composite material comprises carbon nanotubes.
- carbon fibers are placed in multiple layers and are embedded with a polymer resin such as an epoxy-based resin.
- the trailing rotor blade 34 has the function of enhancing the aerodynamic characteristics of the dual fan blade while reducing the weight coefficient of the combined leading rotor blade 32 and the trailing rotor blade 34 (dual fan blade).
- Each rotor blade 32 , 34 includes a root 36 a , 36 b respectively.
- the roots 36 a , 36 b may be combined or separate.
- the leading rotor blade 32 has a tip 38 while the trailing rotor blade 34 has a tip 40 .
- the dual rotor blade 32 , 34 includes a leading edge 42 and a trailing edge 44 .
- a lengthwise gap 48 is defined between the leading rotor blade 32 and the trailing rotor blade 34 .
- the gap is quite small (exaggerated in the drawings) and will generally be in the range of 1% to 5% of the blade pitch.
- the gap may be filled with an elastomer such as rubber.
- the fan 12 in the present embodiment, has a weight advantage over a conventional metal fan, while at the same time having the Foreign Object Damage resistance of a metal fan because the leading rotor blade 32 covers the impacted region of Foreign Object Damage.
- the dual rotor blades 32 and 34 have the further advantage of producing lower pressure losses than a single rotor blade with the aerodynamic loading or turning.
- Further advantages of the fan 12 include that wakes produced thereby may be weaker than those of the equivalent single rotor design, and as such will reduce the fan noise.
- the fan noise may be further reduced by optimising the loading balance between the leading rotor blade 32 and the trailing rotor blade 34 .
- Fan flutter is a challenging design issue for transonic fans.
- the dual fan concept that is described herein provides a further degree of freedom to tune the leading, upstream rotor blade 32 and the trailing, downstream rotor blade 34 .
- FIG. 3 and FIG. 4 illustrate alternate designs with the type of tuning that may be possible.
- FIG. 3 illustrates the clocking of the trailing rotor blade 34 where arrow 50 illustrates the possible circumferential movement of the trailing rotor blade 34 relative to the leading rotor blade 32 , to change the relative angular position of the trailing rotor blade 34 with regard to the leading rotor blade 32 .
- arrow 60 illustrates the axial movement that the trailing rotor blade 34 can achieve such that the trailing rotor blade 34 can overlap with the leading rotor blade 32 thus reducing the chord length of the dual blade while changing the angle thereof.
- trailing rotor blade 34 may act as an aileron relative to the leading rotor blade 32 and may be tuned for ultimate aerodynamic performance.
- the dual blade concept is shown as a fan, described herein above. However it is contemplated that the same concept may be applied to compressor or turbine rotors.
Abstract
Description
Claims (10)
Priority Applications (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US13/789,794 US9410438B2 (en) | 2013-03-08 | 2013-03-08 | Dual rotor blades having a metal leading airfoil and a trailing airfoil of a composite material for gas turbine engines |
CA2844369A CA2844369C (en) | 2013-03-08 | 2014-02-28 | Rotor blades for gas turbine engines |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US13/789,794 US9410438B2 (en) | 2013-03-08 | 2013-03-08 | Dual rotor blades having a metal leading airfoil and a trailing airfoil of a composite material for gas turbine engines |
Publications (2)
Publication Number | Publication Date |
---|---|
US20140255197A1 US20140255197A1 (en) | 2014-09-11 |
US9410438B2 true US9410438B2 (en) | 2016-08-09 |
Family
ID=51488032
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US13/789,794 Active 2034-12-17 US9410438B2 (en) | 2013-03-08 | 2013-03-08 | Dual rotor blades having a metal leading airfoil and a trailing airfoil of a composite material for gas turbine engines |
Country Status (2)
Country | Link |
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US (1) | US9410438B2 (en) |
CA (1) | CA2844369C (en) |
Families Citing this family (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
FR3079007B1 (en) * | 2018-03-14 | 2020-11-20 | Safran Aircraft Engines | SET FOR ONE BLOWER |
US20240044253A1 (en) * | 2022-08-04 | 2024-02-08 | General Electric Company | Fan for a turbine engine |
Citations (23)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US2406460A (en) * | 1943-02-15 | 1946-08-27 | Curtiss Wright Corp | Dual rotation propeller system |
US3850545A (en) | 1972-09-07 | 1974-11-26 | Hayes Albion Corp | Flex fan |
US3860362A (en) | 1973-12-14 | 1975-01-14 | Ford Motor Co | Flexible bladed fan |
US3867062A (en) * | 1971-09-24 | 1975-02-18 | Theodor H Troller | High energy axial flow transfer stage |
US3901625A (en) | 1973-08-27 | 1975-08-26 | Walker Manufacturing Company | Self-adjusting fan vane |
US3914069A (en) | 1973-06-06 | 1975-10-21 | Fort Worth Pressed Steel Corp | Axial flow fan having fully streamlining flexible blades |
US3915591A (en) | 1971-12-09 | 1975-10-28 | Aisin Seiki | Flexible blade fan |
US4037987A (en) | 1975-06-30 | 1977-07-26 | Fram Corporation | Flexible bladed fan with increased natural frequency |
US4172693A (en) | 1977-10-07 | 1979-10-30 | Wallace Murray Corporation | Flexible bladed fan construction |
US4981414A (en) * | 1988-05-27 | 1991-01-01 | Sheets Herman E | Method and apparatus for producing fluid pressure and controlling boundary layer |
US5449273A (en) * | 1994-03-21 | 1995-09-12 | United Technologies Corporation | Composite airfoil leading edge protection |
US5486096A (en) * | 1994-06-30 | 1996-01-23 | United Technologies Corporation | Erosion resistant surface protection |
US6099245A (en) * | 1998-10-30 | 2000-08-08 | General Electric Company | Tandem airfoils |
US6200092B1 (en) * | 1999-09-24 | 2001-03-13 | General Electric Company | Ceramic turbine nozzle |
US6471485B1 (en) * | 1997-11-19 | 2002-10-29 | Mtu Aero Engines Gmbh | Rotor with integrated blading |
US6607358B2 (en) | 2002-01-08 | 2003-08-19 | General Electric Company | Multi-component hybrid turbine blade |
US20050109011A1 (en) * | 2003-07-17 | 2005-05-26 | Snecma Moteurs | De-icing device for turbojet inlet guide wheel vane, vane provided with such a de-icing device, and aircraft engine equipped with such vanes |
US20060018753A1 (en) * | 2004-07-20 | 2006-01-26 | Menian Harry H | High pressure tandem turbine |
US20060093464A1 (en) * | 2004-10-29 | 2006-05-04 | Moniz Thomas O | Counter-rotating gas turbine engine and method of assembling same |
US20080075602A1 (en) | 2006-05-25 | 2008-03-27 | Smiths Aerospace Limited | Blades |
US7736131B1 (en) * | 2008-07-21 | 2010-06-15 | Florida Turbine Technologies, Inc. | Turbine blade with carbon nanotube shell |
US7997870B2 (en) | 2007-08-14 | 2011-08-16 | B N Balance Energy Solutions, Llc | Turbine rotor for electrical power generation |
US20110255987A1 (en) | 2010-04-14 | 2011-10-20 | Ocean Rich Electricity Product Company | Compound balde of a fan |
-
2013
- 2013-03-08 US US13/789,794 patent/US9410438B2/en active Active
-
2014
- 2014-02-28 CA CA2844369A patent/CA2844369C/en active Active
Patent Citations (23)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US2406460A (en) * | 1943-02-15 | 1946-08-27 | Curtiss Wright Corp | Dual rotation propeller system |
US3867062A (en) * | 1971-09-24 | 1975-02-18 | Theodor H Troller | High energy axial flow transfer stage |
US3915591A (en) | 1971-12-09 | 1975-10-28 | Aisin Seiki | Flexible blade fan |
US3850545A (en) | 1972-09-07 | 1974-11-26 | Hayes Albion Corp | Flex fan |
US3914069A (en) | 1973-06-06 | 1975-10-21 | Fort Worth Pressed Steel Corp | Axial flow fan having fully streamlining flexible blades |
US3901625A (en) | 1973-08-27 | 1975-08-26 | Walker Manufacturing Company | Self-adjusting fan vane |
US3860362A (en) | 1973-12-14 | 1975-01-14 | Ford Motor Co | Flexible bladed fan |
US4037987A (en) | 1975-06-30 | 1977-07-26 | Fram Corporation | Flexible bladed fan with increased natural frequency |
US4172693A (en) | 1977-10-07 | 1979-10-30 | Wallace Murray Corporation | Flexible bladed fan construction |
US4981414A (en) * | 1988-05-27 | 1991-01-01 | Sheets Herman E | Method and apparatus for producing fluid pressure and controlling boundary layer |
US5449273A (en) * | 1994-03-21 | 1995-09-12 | United Technologies Corporation | Composite airfoil leading edge protection |
US5486096A (en) * | 1994-06-30 | 1996-01-23 | United Technologies Corporation | Erosion resistant surface protection |
US6471485B1 (en) * | 1997-11-19 | 2002-10-29 | Mtu Aero Engines Gmbh | Rotor with integrated blading |
US6099245A (en) * | 1998-10-30 | 2000-08-08 | General Electric Company | Tandem airfoils |
US6200092B1 (en) * | 1999-09-24 | 2001-03-13 | General Electric Company | Ceramic turbine nozzle |
US6607358B2 (en) | 2002-01-08 | 2003-08-19 | General Electric Company | Multi-component hybrid turbine blade |
US20050109011A1 (en) * | 2003-07-17 | 2005-05-26 | Snecma Moteurs | De-icing device for turbojet inlet guide wheel vane, vane provided with such a de-icing device, and aircraft engine equipped with such vanes |
US20060018753A1 (en) * | 2004-07-20 | 2006-01-26 | Menian Harry H | High pressure tandem turbine |
US20060093464A1 (en) * | 2004-10-29 | 2006-05-04 | Moniz Thomas O | Counter-rotating gas turbine engine and method of assembling same |
US20080075602A1 (en) | 2006-05-25 | 2008-03-27 | Smiths Aerospace Limited | Blades |
US7997870B2 (en) | 2007-08-14 | 2011-08-16 | B N Balance Energy Solutions, Llc | Turbine rotor for electrical power generation |
US7736131B1 (en) * | 2008-07-21 | 2010-06-15 | Florida Turbine Technologies, Inc. | Turbine blade with carbon nanotube shell |
US20110255987A1 (en) | 2010-04-14 | 2011-10-20 | Ocean Rich Electricity Product Company | Compound balde of a fan |
Also Published As
Publication number | Publication date |
---|---|
US20140255197A1 (en) | 2014-09-11 |
CA2844369C (en) | 2022-09-20 |
CA2844369A1 (en) | 2014-09-08 |
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